POS0865 THE EFFECT OF SILVER FIBER GLOVES ON RAYNAUD’S PHENOMENON IN PATIENTS WITH SYSTEMIC SCLEROSIS: A DOUBLE-BLIND RANDOMIZED CROSS-OVER TRIAL.
Authors: S. Liem, E. Hoekstra, F. Bonte-Mineur, C. Magro Checa, A. Schouffoer, C. Allaart, T. Huizinga, S. A. Bergstra, J. De Vries-Bouwstra
Journal: Annals of the Rheumatic Diseases (2022)

Background Over 90% of patients with systemic sclerosis (SSc) experience Raynaud’s phenomenon (RP), which strongly influences quality of life. Therapeutic options of RP include drug treatment and general lifestyle measures such as smoking cessation and avoiding cold by wearing warm clothes and gloves including electrically heated gloves or silver fiber gloves. Clinical observations suggest an additional benefit of silver fiber gloves compared to normal gloves. Silver is thought to help by reflecting heat back into the hands allowing less heat to escape and has an antimicrobial effect. Despite its generalized use among SSc patients, no objective evidence regarding its superiority for RP over normal gloves exists. Objectives To evaluate the added value of 8% silver fiber gloves compared to normal gloves in the treatment of patients with RP secondary to SSc. Methods This was a multicenter double-blind randomized cross-over trial in which 85 SSc patients were randomized in two sequences: 8% silver fiber gloves in period 1 and normal gloves in period 2 or vice versa; each period lasted six weeks. To reduce bias of interindividual differences and external factors (e.g. temperature), a cross-over design was performed in the Netherlands during the winter months. The primary outcome was the triweekly Raynaud Condition Score (RCS), a scale from 1 (no symptoms) to 10 (extreme symptoms). A linear mixed model was used with RCS as dependent and type of gloves as independent variable, adjusted for baseline RCS. Secondary outcome measures included number of RP attacks, RP attack duration, Health Assessment Questionnaire (HAQ-DI) and vascular complications. Secondary outcomes were also analyzed with linear mixed models. All analyses were performed and interpreted before unblinding. Results The 85 included SSc patients had a mean age of 60 (SD:12), 80% were female, 60% had limited cutaneous SSc and 67% used vasoactive medication. Ten patients prematurely ended the study due to various reasons, most notable: allergic reaction to gloves (n=2). At baseline, mean RCS was 6.43 (SD 1.6), with silver fiber gloves the mean RCS decreased to 3.91 (SD 2.3) and with normal gloves to 3.90 (SD 2.3) (Figure 1). No statistically significant difference in RCS during follow-up was observed between the silver fiber gloves and normal gloves (β 0.067, 95% CI -0.006 to 0.19), meaning that on the 1-10 scale, silver fibre gloves gave only a 0.067 higher RCS compared to normal gloves (Table 1). For all other secondary outcome measures, we did not find a statistically significant difference between silver fiber gloves and normal gloves, except for the HAQ (β 0.036, 95% CI 0.026 to 0.046; Table 1), which is not clinically relevant. One vascular complication occurred in the silver fiber gloves, compared to three vascular in the normal gloves, which was not statistically significant different (OR:3.2, 95% CI 0.32 to 31.1). Table 1. Primary and secondary efficacy outcomes β 95% confidence interval Primary outcome Raynaud Condition Score 0.067 -0.0059; 0.194 Secondary outcomes Raynaud attacks frequency -0.480 -1.215; 0.255 Raynaud attacks duration 39.80 -36.051; 115.654 VAS warmth hands -0.086 -0.212; 0.041 Impact Raynaud 0.088 -0.035; 0.211 HAQ_DI 0.036 0.026; 0.046 VAS: visual analogue scale; HAQ: Health Assessment Questionnaire The reference category was Normal gloves. Linear mixed models were performed with the primary and secondary outcomes as dependent variables, the type of gloves as independent variable, adjusted for baseline Raynaud Condition Score. Figure 1. Raynaud Condition Score during the study period Conclusion This trial shows that wearing any type of glove decreases the RP burden in SSc patients, but no additional benefit from gloves containing 8% silver fibers compared to normal gloves could be demonstrated. Potentially, less vascular complications may arise in SSc patients wearing silver fiber gloves. Further confirmation of this potential benefit is necessary. Acknowledgements The authors would like to thank all participants of this study and Skafit for providing the gloves. Disclosure of Interests None declared